Description
These homemade Costco-style chocolate muffins are rich, moist, and packed with deep chocolate flavor, mimicking the indulgent bakery muffins from Costco.
Ingredients
- 1 2/3 cups all-purpose flour
- 2 teaspoons baking powder
- 1/2 teaspoon baking soda
- 1 teaspoon kosher salt
- 3/4 cup unsweetened cocoa powder, divided
- 1/2 cup hot water
- 1 cup granulated sugar
- 1/3 cup vegetable oil
- 2 large eggs plus 1 yolk, at room temperature
- 2 teaspoons pure vanilla extract
- 3/4 cup sour cream, at room temperature
- 15 ounces semi-sweet chocolate chips, about 2 1/2 cups, divided
Instructions
- Preheat the oven to 375°F (190°C). Line a 6-cup jumbo muffin tin with liners or grease each cup.
- Whisk 1/4 cup cocoa powder with hot water in a small bowl until smooth and set aside to cool.
- In a medium bowl, whisk flour, remaining cocoa powder, baking powder, baking soda, and salt.
- In a large bowl, whisk sugar, vegetable oil, eggs, yolk, and vanilla until smooth.
- Stir in sour cream and cooled cocoa mixture until incorporated.
- Gradually stir in dry ingredients until just combined, avoiding overmixing.
- Fold in 2 cups of chocolate chips, reserving 1/2 cup for topping.
- Divide batter evenly in muffin cups, filling each about 3/4 full. Top with reserved chocolate chips.
- Bake for 25–30 minutes, or until a toothpick comes out clean.
- Cool muffins in the pan for 5 minutes before transferring to a wire rack to cool completely.
Notes
- Use natural, unsweetened cocoa for best results.
- Full-fat Greek yogurt can substitute sour cream, with slight flavor changes.
- Store in an airtight container at room temperature for 3 days or refrigerate for a week.
- Freeze individually wrapped muffins for up to 3 months.
- Batter can be prepped and refrigerated up to 24 hours in advance.
Nutrition
- Serving Size: 1 jumbo muffin
- Calories: 580
- Sugar: 40g
- Sodium: 320mg
- Fat: 32g
- Saturated Fat: 15g
- Unsaturated Fat: 14g
- Trans Fat: 0g
- Carbohydrates: 70g
- Fiber: 5g
- Protein: 7g
- Cholesterol: 65mg
